package com.jdd.common.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5Util {

	public static String byteArrayToHexString(byte b[]) {
		StringBuffer resultSb = new StringBuffer();
		for (int i = 0; i < b.length; i++){
			resultSb.append(byteToHexString(b[i]));
		}
		return resultSb.toString();
	}

	private static String byteToHexString(byte b) {
		int n = b;
		if (n < 0) {
			n += 256;
		}
		int d1 = n / 16;
		int d2 = n % 16;
		return hexDigits[d1] + hexDigits[d2];
	}

	public  static String encode(String password){
		try {
			MessageDigest digest = MessageDigest.getInstance("MD5");
			byte[] result = digest.digest(password.getBytes());
			StringBuilder sb = new StringBuilder();
			for (byte b : result) {
				int number = b & 0xff; //加盐 | 0x23
				String str = Integer.toHexString(number);
				if(str.length()==1){
					sb.append("0");
				}
				sb.append(str);
			}
			return sb.toString();
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
			return "";
		}
	}

	public static String MD5Encode(String origin, String charsetname) {
		String resultString = null;
		try {
			resultString = new String(origin);
			MessageDigest md = MessageDigest.getInstance("MD5");
			if (charsetname == null || "".equals(charsetname)) {
				resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
			} else {
				resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
			}
		} catch (Exception exception) {
		}
		return resultString;
	}

	private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5",
			"6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

}
